>>1
If you plan to tackle a real project, Scheme will be frustrating with its lack of libraries. On the other hand, you can find almost everything you need in CL.
There are maybe a few exceptions, Racket, Chicken, Guile and Gerbil are the first to come to my mind but they're all far from CL's ecosystem. You should start with reading SICP nonetheless, you'll learn a bit of Lisp, of which both Scheme and CL are dialects.